This relates generally to graphics processing.
In a variety of different circumstances, the colors that will be shown on a display need to be adjusted. Examples of such adjustments includes skin tone adjustments, color temperature adjustments, and color saturation adjustments, to mention a few examples.
Typically these color transformations are implemented using a three-dimensional lookup table. The problem with three-dimensional lookup tables is that the dimensions of the lookup table are a function of the number of input color components in the chosen color space. As an example, a lookup table for sRGB color space requires three inputs and hence uses a three-dimensional lookup table. The size of such a lookup table is 48 megabytes when both input and output are in the sRGB space with a depth of 8 bits per color.
Thus the use of three-dimensional lookup tables involves an enormous burden in terms of memory capacity and memory bandwidth requirements.